THE PROBLEM OF ESTIMATING THE UNCERTAINTY OF THE FIXED POINT TEMPERATURE DUE TO THE PRESENCE OF IMPURITIES

摘要

The main problems in estimating the uncertainty due to the presence of impurities in the material: the absence in the documents of a unique definition of the quantity being measured ~ the fixed point temperature, the lack of agreed methods of realizing the fixed points and the insufficient justification of the equations used for the estimate, are analyzed. The results of a measurement of the melting point of gallium are presented, which differ in the conditions in which they were realized - with one and two liquid-solid interfaces and different solidification conditions, are presented. The reasons for the considerable difference between the values of the temperatures obtained in these experiments are discussed.